[Jeff]

When one refers to the inclined plane (and thinks of different planes eg. elbow plane and turned shoulder plane), do you envisage the inclined plane being relevant to the clubshaft's movements in space and/or do you envisage that it refers to the imaginary PP#3-sweetspot axis line's movements in space?

When one talks of tracing a SPL, what is actually tracing the SPL, and why that part? Does one trace a SPL to control the movement of the clubshaft in space, or the clubhead in space, or the clubface sweetspot in space?

Jeff.